Thursday, November 16, 2017

Models and Types on MyFlightbook

Models on MyFlightbook capture a lot of information about an aircraft so that you don't have to log it explicitly.  Capturing this information in the model means that the system can draw a straight line from the tailnumber (registration) of the aircraft you fly to the model of that aircraft has two distinct advantages: (a) you don't have to pointlessly go to the effort of logging information that the system can easily derive, and (b) it avoids errors if you log impossible things, such as multi-engine turbine time in a Piper cub.  After all, for example, A Boeing 737 is inherently multi-engine/turbine (jet)/high-performance, so time in it absolutely should (and does) accrue to your totals in each of those categories.

Models capture several details for an aircraft, including:
  • The name of the model ("C-172 N", for example)
  • The "marketing" name ("Skyhawk" for a C-172, "Dreamliner" for a Boeing 787).  Many (most?) aircraft don't have a separate marketing name, so it's fine to leave this blank.  Good rule of thumb: if it repeats the manufacturer or model name, just leave it blank.
  • An ICAO identifier.  Confusingly (as discussed below), this is sometimes called a "type", but on MyFlightbook it is always referred to as "ICAO".  This is what you'd file on a flight plan, and is never more than four letters/numbers.  E.g., a C-172 S and a C-172 P both have an ICAO code of  "C172".
  • The category/class for the model (Airplane Single Engine Land, for a C-172)
  • "Interesting" characteristics, such as whether it is high performance, tailwheel, complex, all-glass (no steam-gauge versions were ever produced), turbine, etc.
All of the  above is used for computing totals and currency, but there's one additional attribute of a model that probably causes more confusion than any other: the "Type" field.

Many pilots, when creating/editing a model repeat the model name here.  Some even put the specific registration/tailnumber of the aircraf they want.  But the "Type" field has a very specific purpose on MyFlightbook: it provides a grouping mechanism for aircraft that require a type rating to fly.

A license generally provides privileges to fly a specific category and class of aircraft*, such as "Airplane, Single Engine Land (ASEL)".  More sophisticated aircraft - typically jets or anything over 12,500lbs - require a type rating to fly.  That is, a specific license to fly that particular model of aircraft.  Furthermore, to be legal to fly it, you have to have recent flight experience in that particular model of aircraft as well.

For example, in the US, 61.57(a) says:
(a)General experience.

(1) Except as provided in paragraph (e) of this section, no person may act as a pilot in command of an aircraft carrying passengers or of an aircraft certificated for more than one pilot flight crewmember unless that person has made at least three takeoffs and three landings within the preceding 90 days, and -
(i) The person acted as the sole manipulator of the flight controls; and
(ii) The required takeoffs and landings were performed in an aircraft of the same category, class, and type (if a type rating is required), and, if the aircraft to be flown is an airplane with a tailwheel, the takeoffs and landings must have been made to a full stop in an airplane with a tailwheel.

So, for example, if you want to fly passengers in a Piper Seneca (a small twin-engine airplane), you merely have to have done three takeoffs + landings in a multi-engine aircraft within the 90 days preceding the flight.  Any multi-engine aircraft will do.

But note the bold-faced wording above.  A 737 requires a type rating, a Piper Seneca does not.  So if you do 3 takeoffs/landings in a 737, you are fine for carrying passengers in a Seneca.  But the reverse is not true: if you do your three takeoffs/landings in a Seneca, you are not OK to carry passengers in the 737.

Enter the "Type" field.  Boeing 737's share a common type rating.  That is, the B737-300 and the B737-900 are interchangeable from a type perspective.  For this reason, all of these models have "B737" in the "Type" field.  Thus, if you do 2 takeoffs/landings in a B737-300 and one in a B737-900, all three takeoffs/landings count towards your 61.57(a) currency and you are current to carry passengers in a B737.

So it's safe to view the "type" field as satisfying the following rules:
  • If a model of aircraft does NOT require a type rating, it should be blank.  Think C-172, Piper Seneca, pretty much any glider, etc.
  • If a model of aircraft requires a type rating, it should have a non-blank value for the "type" field that is shared with other aircraft that share a common type rating.  The Boeing 757 and 767, for example, have a common type rating, so the "type" field for all of the variants of these two aircraft is "B757, B767".
  • If a model of aircraft requires a type rating, the "type" field must be distinct from other aircraft that require a different type rating.  So, for example, the Boeing 737 and the Boeing 747 MUST have different "type" fields, since they require different type ratings.
Beyond that, there's no real requirement.  There's no inherent reason, for example, that Boeing 737's in the system couldn't have a "type" field of "Fred Flintstone" and Boeing 757's have "Wilma Flinstone", but for the sake of making things consistent and a bit more self explanatory, we generally follow FAA guidelines for "type" designations.  Hence the Boeing 737 has a type designation of "B737", and the Airbus A380 has "A380".

Interestingly (in the US at least), the Robinson R22 and R44 do not technically require a type rating, but the currency requirements effectively mimic a type rating.  For this reason, these two helicopter models have a "type" field of R22 and R44 (respectively).

In any case, when in doubt, just leave this field empty.  I review EVERY new model (or model modification), so I will generally catch issues here.

*In some parts of the world, you effectively need a separate license - or at least sign-off - for each model of aircraft you wish to fly, and currency must be maintained in each such model.  MyFlightbook has an option to support this.

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